:root {
  --bg: #f6f5fb;
  --card: #ffffff;
  --text: #1d1b2c;
  --muted: #6b6880;
  --line: #e4e1ef;
  --accent: #6d4aff;
  --accent-2: #ff5aa5;
  --accent-soft: #efeaff;
  --chip: #f1eff8;
  --code-bg: #f4f2fb;
  --error: #d6336c;
  --shadow: 0 1px 2px rgba(30, 20, 80, .05), 0 6px 24px rgba(30, 20, 80, .06);
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #12111a;
    --card: #1c1a27;
    --text: #ecebf5;
    --muted: #9c98b3;
    --line: #2e2b3d;
    --accent: #9b83ff;
    --accent-2: #ff7ab8;
    --accent-soft: #2a2442;
    --chip: #262335;
    --code-bg: #15131f;
    --error: #ff7a9c;
    --shadow: none;
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", sans-serif;
  line-height: 1.6;
  font-size: 15px;
}
a { color: var(--accent); }
code { background: var(--code-bg); padding: 1px 5px; border-radius: 4px; font-size: .9em; }
[hidden] { display: none !important; }

.wrap { max-width: 920px; margin: 0 auto; padding: 0 16px; }
.wrap.narrow { max-width: 520px; padding-top: 40px; }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 20px;
  margin: 16px 0;
  box-shadow: var(--shadow);
}
h1 { font-size: 22px; margin: 0 0 8px; }
h2 { font-size: 18px; margin: 0 0 6px; }
h3 { font-size: 15px; margin: 18px 0 6px; }
.muted { color: var(--muted); }
.small { font-size: 13px; }
.error { color: var(--error); }

/* Gate */
.gate { min-height: 100vh; display: grid; place-items: center; padding: 16px; }
.gate-card { width: 100%; max-width: 360px; text-align: center; }
.gate-card input { text-align: center; margin: 8px 0 12px; }
.logo { font-size: 30px; }

/* Topbar */
.topbar { background: var(--card); border-bottom: 1px solid var(--line); position: sticky; top: 0; z-index: 10; }
.topbar-inner { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding-top: 10px; padding-bottom: 10px; flex-wrap: wrap; }
.brand { display: flex; align-items: center; gap: 8px; font-weight: 700; }
.brand .logo { font-size: 22px; }
.tabs { display: flex; gap: 4px; }
.tab { border: 0; background: transparent; color: var(--muted); padding: 6px 12px; border-radius: 8px; font: inherit; cursor: pointer; }
.tab.active { background: var(--accent-soft); color: var(--accent); font-weight: 600; }

/* Stepper */
.stepper { list-style: none; display: flex; gap: 6px; padding: 0; margin: 20px 0 0; }
.stepper li { flex: 1; display: flex; align-items: center; gap: 6px; font-size: 13px; color: var(--muted); padding: 8px 10px; border-radius: 10px; background: var(--chip); cursor: pointer; white-space: nowrap; }
.stepper li span { display: inline-grid; place-items: center; width: 22px; height: 22px; border-radius: 50%; background: var(--line); color: var(--text); font-size: 12px; font-weight: 700; flex: none; }
.stepper li.active { background: var(--accent-soft); color: var(--accent); font-weight: 600; }
.stepper li.active span, .stepper li.done span { background: var(--accent); color: #fff; }

/* Form */
.field { display: block; margin: 14px 0; font-weight: 600; font-size: 14px; }
.field .label { margin-bottom: 6px; }
.field em { color: var(--error); font-style: normal; }
input, select, textarea {
  display: block; width: 100%; margin-top: 6px;
  font: inherit; font-weight: 400; color: var(--text);
  background: var(--bg); border: 1px solid var(--line); border-radius: 10px; padding: 10px 12px;
}
textarea { resize: vertical; }
input:focus, select:focus, textarea:focus { outline: 2px solid var(--accent); outline-offset: -1px; }
.grid2 { display: grid; grid-template-columns: 1fr 1fr; gap: 0 14px; }
.check { display: flex; align-items: center; gap: 8px; font-size: 14px; }
.check input { width: auto; margin: 0; }

.chips { display: flex; flex-wrap: wrap; gap: 8px; }
.chip { border: 1px solid var(--line); background: var(--chip); color: var(--text); padding: 6px 12px; border-radius: 999px; font: inherit; font-size: 14px; font-weight: 400; cursor: pointer; }
.chip.on { background: var(--accent); border-color: var(--accent); color: #fff; }

.actions { display: flex; justify-content: space-between; align-items: center; margin-top: 18px; gap: 10px; }
.btn { border: 1px solid var(--line); background: var(--card); color: var(--text); padding: 9px 16px; border-radius: 10px; font: inherit; font-weight: 600; cursor: pointer; }
.btn:hover { border-color: var(--accent); }
.btn.primary { background: linear-gradient(135deg, var(--accent), var(--accent-2)); color: #fff; border: 0; }
.btn.small { padding: 5px 10px; font-size: 13px; }
.btn.block { width: 100%; }
.btn:disabled { opacity: .6; cursor: wait; }
.btn-row { display: flex; gap: 8px; flex-wrap: wrap; }
.row-between { display: flex; justify-content: space-between; align-items: center; gap: 10px; flex-wrap: wrap; }

/* Results */
.summary .tags { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 6px; }
.tag { background: var(--accent-soft); color: var(--accent); padding: 2px 10px; border-radius: 999px; font-size: 13px; }
.scene-head { display: flex; align-items: center; gap: 10px; margin-bottom: 4px; }
.scene-no { background: linear-gradient(135deg, var(--accent), var(--accent-2)); color: #fff; font-weight: 700; border-radius: 8px; padding: 2px 10px; font-size: 13px; }
.picks { display: grid; grid-template-columns: 1fr 1fr; gap: 0 14px; }
.why { background: var(--chip); border-radius: 10px; padding: 10px 12px; font-size: 13px; margin: 6px 0 12px; }
.why b { color: var(--accent); }
.prompt { position: relative; margin-top: 10px; }
.prompt .plabel { font-size: 12px; font-weight: 700; color: var(--muted); display: flex; justify-content: space-between; align-items: center; margin-bottom: 4px; }
.prompt pre { margin: 0; white-space: pre-wrap; word-break: break-word; background: var(--code-bg); border: 1px solid var(--line); border-radius: 10px; padding: 12px; font-family: inherit; font-size: 14px; }
.aiout { white-space: pre-wrap; background: var(--code-bg); border: 1px solid var(--line); border-radius: 10px; padding: 12px; margin-top: 12px; }
details.ai summary { cursor: pointer; list-style: none; display: flex; align-items: baseline; gap: 10px; flex-wrap: wrap; }
details.ai summary::-webkit-details-marker { display: none; }
details.ai summary h2 { margin: 0; }
.tips ul, .prose ul, .prose ol { padding-left: 20px; margin: 6px 0; }

/* Library */
.lib { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-bottom: 20px; }
.lib .item { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 14px; }
.lib .item .code { font-weight: 700; color: var(--accent); cursor: pointer; }
.lib .item .cat { font-size: 12px; color: var(--muted); }
.lib .item p { margin: 6px 0 0; font-size: 14px; }
.lib .item .en { color: var(--muted); font-size: 13px; }

.foot { padding: 10px 16px 30px; text-align: center; }

.toast { position: fixed; left: 50%; bottom: 24px; transform: translateX(-50%); background: var(--text); color: var(--bg); padding: 8px 16px; border-radius: 999px; font-size: 14px; z-index: 50; }

@media (max-width: 640px) {
  .grid2, .picks, .lib { grid-template-columns: 1fr; }
  .stepper li { font-size: 0; justify-content: center; }
  .stepper li span { font-size: 12px; }
  .stepper li.active { font-size: 13px; }
  .card { padding: 16px; }
}